Corrugated paperboard dishware and cookware

ABSTRACT

Disposable dishware and cookware may be constructed from corrugated paperboard. The corrugated paperboard provides voids filled with air to serve as a natural insulation barrier. In so doing the contents held by the dishware are maintained at a desired temperature longer without transferring temperature to the user. The voids may also serve as conduits or plenums to communicate hot air away from the cookware and thus provide for use at elevated temperatures.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This non-provisional application claims the priority benefits of provisional U.S. patent application Ser. No. 60/377,825, filed on May 3, 2002.

FIELD OF THE DISCLOSURE

[0002] The disclosure generally relates to dishware and cookware and, more particularly, relates to disposable dishware and cookware.

BACKGROUND OF THE DISCLOSURE

[0003] Disposable dishware is widely used. For example, paper plates are ubiquitous at such events as picnics, barbecues and many other social gatherings. Paper cups are used for everything from in-home drinks to dentists offices to fast food restaurants. Milk cartons and restaurant take-out packages are often made of paper material coated with a fluid impermeable layer.

[0004] One difficulty associated with such items, however, is related to insulation. Taking a paper cup as an example, their use is somewhat limited when it comes to maintaining the temperature of the drink held therein. Coffee is often sold in disposable cups, but typically in the form of Styrofoam, or the like. Not only is it desirable to keep the contents warm and/or cold, but it is also desirable to limit dissipation of such temperature to the hand of the user. As a result, various after market devices have been introduced and been met with substantial commercial success. Foam coolers sized to correspond to the outer dimension of the cup are currently sold and provide a snug and insulative fit. Cardboard rings are often provided by coffee shops for fitting around the outside of the paper coffee cup to thereby provide an added barrier to limit heat transference to the hand of the users. However, both such solutions add additional apparatus to the process at both added expense and user burden.

[0005] Paper cookware is even more limited. As such items must be exposed to high temperatures, the paper is limited to applications which will not exceed its combustion point, approximately 450° F. Moreover, cookware such as pans and plates are often subjected not only to high temperatures, but below freezing temperatures as well. Paper is limited in this regard as well in that as the food contained within the dish freezes, it often expands due to the water contained therein, and the paper is of insufficient strength to withstand the forces of expansion. Ice cream cartons, for example, are therefore often oversized provided with reinforcing ribs or expansion joints to address such issues.

[0006] In light of the foregoing shortcomings, the use of paper in dishware and cookware has been less than fully exploited. Even though the paper itself is relatively inexpensive and lends itself to disposability and recycling, such limitations have prevented the breadth of disposable cookware options available to the consuming public, and required use of more expensive, and less than optimal, metals and the like.

SUMMARY OF THE DISCLOSURE

[0007] In accordance with one aspect of the disclosure, disposable paper based dishware and cookware are provided. The paper based dishware may be provided in the form of a cup formed from corrugated paperboard. The corrugations of the paperboard create voids which serve as an insulation layer between the user and the cup contents. The paper based cookware may be provided in the form of a pan formed from corrugated paperboard as well. The corrugation of the paperboard not only creates voids which may be filled with air or another insulating material, but also serve as cooling conduits or pseudo-chimneys enabling heat to dissipate from the paper to the air within the voids and ultimately to be directed away from the cookware.

[0008] In accordance with another aspect of the disclosure, an insulated food container is disclosed which comprises a bottom wall, and an upstanding outer wall attached to the bottom wall having an interior space. The outer wall includes an inner layer, an outer layer, and a corrugated layer between the inner layer and outer layer defining voids with the interior space being insulated from the atmosphere by the outer wall and the voids in the corrugated layer.

[0009] In accordance with another aspect of the disclosure, an insulated container manufactured from cellulosic materials is disclosed which comprises a bottom wall and an upstanding outer wall attached to the bottom wall in defining a mouth and an interior space. The outer wall includes a corrugated layer and at least one substantially planar layer attached to the corrugated layer. The corrugated layer includes a plurality of flutes forming voids in cooperation with the planar layer.

[0010] In accordance with another aspect of the disclosure, a method of cooking a food stuff is disclosed which comprises disposing a food stuff in a container manufactured in cellulosic materials, and warming the food stuff within the container. The container may include a bottom wall and upstanding outer wall with the outer wall including an inner layer, an outer layer, and a corrugated layer between the inner layer and the outer layer defining voids.

[0011] In accordance with yet another aspect of the disclosure, a method of evenly cooling a food stuff is disclosed which comprises disposing of food stuff within a container, placing the container in an atmosphere cooler than the temperature of the food stuff, and allowing the heat of the food stuff to dissipate within voids of the outer wall and to the atmosphere. The container may include an outer wall including an outer layer, an inner layer, and a corrugated layer between the inner layer and the outer layer defining the voids.

[0012] These and other aspects and features of the disclosure will become more apparent upon reading the following detailed descriptions when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is an isometric view of a disposable cup constructed in accordance with the teachings of the disclosure;

[0014]FIG. 2 is an isometric view of a cap for the disposable cup.

[0015]FIG. 3 is an isometric view of the cup and cap assembled.

[0016]FIG. 4 is cross-sectional view of the cup of FIG. 1, taken along line 4-4 of FIG. 1;

[0017]FIG. 5 is an isometric view of a disposable pan constructed in accordance with the teachings of the disclosure;

[0018]FIG. 6 is a cross-sectional view of the pan of FIG. 3, taken along line 6-6 of FIG. 3; and

[0019]FIG. 7 is a cross-sectional view of an outer wall having more than one corrugated layer.

[0020] While the disclosure is susceptible to various modifications and alternative constructions, certain illustrative embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however, that there is no intention to limit the disclosure to the specific forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

[0021] Referring now to the drawings, and with specific reference to FIGS. 1-3, a disposable dish constructed in accordance with the teachings of the disclosure is generally referred to by reference numeral 20. While the dish 20 is depicted in the form of a cup in FIG. 1, it is to be understood that dish could be provided in any other form wherein insulation properties are desirable such as, but not limited to plates, bowls, saucers, servers, casseroles, platters, and the like.

[0022] The cup 20 may include a frustoconical outer wall 22 closed by a base 24. The outer wall 22 need not be frustoconical in shape but could be any number of other shapes including, but not limited to, straight conical, angular, or the like. The cup 20 may further include a brim 26 defining a mouth 28 for access to an interior space 30 for holding foodstuffs or drinks such a coffee, tea, soda, etc. The cup 20 may be provided with a lid 32 adapted to substantially close off the mouth 28 upon fitting to the cup, and which may include a relatively small port 34, or reclosable flap (not shown) to allow for access to the liquid contained within the cup 20 when the lid 32 is mounted to the cup 20.

[0023] Turning now to FIG. 4, the cup 20 is illustrated in cross-section. As shown therein, the outer wall 22 may be formed from corrugated paperboard. More specifically, the outer wall 22 may include an inner layer 36, and outer layer 38, and a layer 40 of corrugations or flutes 42 traveling longitudinally from the base 24 to the brim 26. In so doing, the corrugations 42 form a plurality of voids 44. The voids 44 may be filled with air which by itself serves as a temperature barrier or insulation layer inhibiting transfer of heat and/or cold from the interior space 30 to and from the atmosphere 46. The voids 44 could, alternatively, be filled with some other insulative material such as, but not limited to, foam styrene, to further enhance the insulative properties of the cup 20. The base 24 can also be formed of similar corrugated paperboard.

[0024] In further alternative embodiments, the outer wall 22 may include one or more additional layers of corrugated material to provide even more insulative capability. Such layers could be of various depth and spacing. The corrugations also could travel circumferentially around the cup 20, as opposed to longitudinally. The various layers of corrugations could also be configured in differing or alternating orientations, or be provided at differing or alternating dimensions.

[0025] By manufacturing the cup 20 from corrugated paperboard, the cost of the cup 20 is maintained at sufficiently low level so as to be disposable. Moreover, the use of cellulosic material makes the cup easily recyclable. The use of corrugated paperboard affords a built-in insulation feature removing the need for aftermarket accessories such as coolers or slip-on protective coats.

[0026] As indicated above the use of corrugated paperboard is not limited to dishware according the teachings of this disclosure. Cookware and serveware are also encompassed. As illustrated in FIG. 3, the cookware may be provided as a pan 50. While the following description will be made with reference to the pan 50, it is to be understood that the terms cookware and serveware, and the teachings of this disclosure are applicable to many other forms including, but not limited to, pots, skillets, woks, griddles, casseroles, and the like.

[0027] The pan 50 may include a substantially rectangular outer wall 52 having a closed and substantially planar bottom wall 53. The outer wall 52 may terminate at an upper end 54 with a radially outwardly extending lip 56. The lip 56 defines a mouth 58 providing access to an interior space 60. A lid 62 may be provided to close the pan 50 when desired. Moreover, the pan may include, while not depicted in FIG. 3, a plurality of partitions to divide the pan 50 into individual compartments. Such a feature may be particularly advantageous, for example, when heating or freezing a complete meal with an entree in one compartment and side dishes in others.

[0028] As shown in FIG. 4, wherein the pan 50 is depicted in cross-section, the construction of the pan 50 is similar to that of the cup 20. More specifically, the outer wall 52 and bottom wall 53 may be constructed from corrugated paperboard. As with the cup 20, the corrugated paperboard of the pan 50 may include an inner layer 64, an outer layer 66, and a layer 68 of corrugations 70 therebetween. The corrugations create voids 72 which may be filled with air or another insulative material. If the voids 72 are filled with air or some other thermally conductive material, the pan 50 is able to withstand temperatures significantly higher than normal paper products. Whereas normal paper combusts at approximately 451° F., the inventors have found that a pan 50 constructed in accordance with the teachings of the invention can withstand temperatures in excess of 500° F. In so doing, the pan 50 is able to withstand temperatures in excess of the majority of baking and cooking requirements of common dishes.

[0029] Not only can such a pan 50 withstand high temperatures and thus be microwavable or ovenable, such a pan 50 can also be chilled or frozen. This feature is provided, at least in part, by the additional room afforded by the voids 72 provided between the corrugations 70. Such voids allow for the inner layer 64 to radially expand outwardly and compress the corrugations 70 into the voids 72 as the matter held within the pan 50 freezes and expands.

[0030] As with the dishware described above, the pan 50 may be alternatively provided with more than one layer of corrugations, or with corrugations of greater amplitude, frequency or wavelength. Moreover, the multiple layers of corrugations may be provided in alternating transverse directions, or at various degrees of out-of-phase disposition. Multiple grades of cellulosic material can also be used. In addition, if desired, the inner and/or outer layers, respectively, can be coated with liquid impervious, non-stick, or other compounds as well.

[0031] For example, as depicted in FIG. 7, an alternative embodiment of a dishware outer wall is depicted in cross-section. As shown therein, the outer wall 100 may include an inner layer 102, an outer layer 104, and an intermediate layer 106, and first and second layers of corrugations 108 and 110 therebetween. Not only does the wall 100 include multiple layers of corrugations, but it will be further noted that the corrugations of the first and second layers 108 and 110 are provided in different dimensions. More specifically, the amplitudes, frequencies, and wavelengths of the corrugations are different. For example, the corrugations or flutes 112 of the first layer of corrugations 108 include a wavelength of β and amplitude of γ. Whereas the flutes 114 of the second layer of corrugations 110 include a much shorter wavelength of β′ and a much small amplitude of α′.

[0032] In order to form the shape of the cup 20 or pan 50, a conventional thermoforming process can be used. In such a process, paperboard, which has already been corrugated to have the desired number of layers and corrugations of the desired shape and size, is subjected to a thermoforming mold. First and second dies (not shown) having a mating protrusion and cavity in the desired shape are provided, with the corrugated paperboard being positioned therebetween. The paper board is compressed between the dies under heat and pressure sufficient to deform the paperboard into a shape congruent with the dies. Upon retraction of the dies, the paperboard retains the desired shape, whereupon the edges thereof can be trimmed or otherwise finished for sale.

[0033] From the foregoing, one of ordinary skill in the art will readily appreciate that corrugated paperboard dishware, serveware,.and cookware can be constructed based on the teachings of the present disclosure. Moreover, one of ordinary skill in the art will understand that variations on the disclosed embodiments can be produced without departing from the scope and protection afforded by the disclosure. 

What is claimed is:
 1. An insulated, food container manufactured from cellulosic materials, comprising: a bottom wall; and an upstanding outer wall attached to the bottom wall and defining an interior space, the outer wall including an inner layer, an outer layer, and a corrugated layer between the inner layer and outer layer defining voids, the interior space being insulated from the atmosphere by the outer wall and the voids in the corrugated layer.
 2. The container of claim 1, wherein the container is one of a frusto-conical and cylindrical shape.
 3. The container of claim 2, further including a liquid impermeable coating on the inner layer.
 4. The container of claim 1, further including a lid.
 5. The container of claim 1, wherein the container is substantially parallelepiped in shape.
 6. The container of claim 1, wherein the voids contain air, the air being able to circulate within each void.
 7. The container of claim 1, wherein the voids contain foam styrene.
 8. The container of claim 1, wherein the walls are compressible.
 9. The container of claim 1, wherein the bottom wall includes a first layer, a second layer, and a corrugated layer between the two.
 10. The container of claim 1, wherein the outer wall further includes a second corrugated layer.
 11. An insulated container manufactured from cellulosic materials, comprising: a bottom wall; an upstanding outer wall attached to the bottom wall and defining a mouth and an interior space, the outer wall including a corrugated layer and at least one substantially planar layer attached to the corrugated layer, the corrugated layer including a plurality of flutes forming voids in cooperation with the planar layer.
 12. The container of claim 11, wherein the voids contain air.
 13. The container of claim 11, wherein the voids contain foam styrene.
 14. The container of claim 11, further including a second planar layer, the corrugated layer being positioned between the first and second planer layers.
 15. The container of claim 11, further comprising a removable cap adapted to seal the mouth.
 16. The container of claim 14, further including a second corrugated layer.
 17. The container of claim 16, wherein the first and second corrugated layers include flutes provided at different amplitudes.
 18. The container of claim 16, wherein the first and second corrugated layers include flutes provided at different frequencies.
 19. The container of claim 16, wherein the first and second corrugated layers include flutes provided at different wavelengths.
 20. The container of claim 16, wherein the first and second corrugated layers include flutes which are out-of-phase with one another.
 21. The container of claim 19, wherein the flutes are 180° out-of-phase.
 22. A method of cooking a foodstuff, comprising: disposing a foodstuff in container manufactured of cellulosic materials, the container including a bottom wall and an upstanding outer wall, the outer wall including an inner layer, an outer layer, and a corrugated layer between the inner layer and outer layer defining voids; and warming the foodstuff within the container.
 23. The method of claim 22, wherein the foodstuff is warmed to a temperature than exceeds 500° F.
 24. The method of claim 23, wherein the foodstuff is warmed to a temperature that exceeds 451° F.
 25. The method of claim 22, further comprising placing a cap on the container prior to cooking the foodstuff.
 26. A method of evenly cooling a foodstuff, comprising: disposing a foodstuff within a container, the container having an outer wall including an outer layer, an inner layer, and a corrugated layer between the inner layer and outer layer defining voids; placing the container in an atmosphere cooler than the temperature of the foodstuff; and allowing the heat of the foodstuff to dissipate within the voids of the outer wall and to the atmosphere.
 27. The method of claim 26, further comprising freezing the foodstuff.
 28. The method of claim 27, further comprising allowing the outer wall to slightly compress under the expansion of the foodstuff due to freezing. 